Existing industrial hedgers and cutting tools are typically single purpose vehicles that include either a single cutting blade or a plurality of cutting blades that are fixed to either a stationary or a rotating cutting blade arm. These hedgers operate in a single or at most two planes. As a result, such hedgers are limited as to the types of operations they can perform. Where multiple operations are contemplated, the operator is required to change either an attachment or the orientation of the blades. For example, U.S. Pat. No. 2,404,655 to Randall, dated Jul. 23, 1946, describes a Machine for Felling Trees. This machine provides two saws, one mounted horizontally and the other mounted vertically. The horizontal blade is used for felling trees, whereas the vertical blade is used for cutting the felled trees into logs. The two blades are not mounted on the same bearing member and cannot be used concurrently.
A Dec. 11, 1951 patent issued to Miller et al. for Tractor Mounted Brush Saw, U.S. Pat. No. 2,577,906 identifies a machine having two or more saws mounted on a frame positioned at the front end of a tractor. The saws are operated by individual power units, so that the speed of each can be varied independently.
Similarly, U.S. Pat. No. 2,624,380 for Brush Saw to L. N. Haynes, dated Jan. 6, 1953, has two saw blades that are carried forward of the front end of a tractor. Although each saw blade assembly may be tilted upwardly from a horizontal position, there appears to be no structure which would allow for the blades to be positioned alongside the tractor.
Vertically-Adjustable Tree-Felling Tractor Mounted Saw was issued to Ryals on Dec. 1, 1953, as U.S. Pat. No. 2,661,035. This invention describes a saw blade apparatus attached to the front end of a tractor. The assembly includes a frame that allows the single blade to be raised or lowered and to be moved sideways from one front corner of the tractor to the opposite front corner. The structure of this invention does not permit the blade to be moved to the side of the tractor or to be tilted from the horizontal to the vertical.
Whitmore obtained U.S. Pat. No. 2,940,486 on Jun. 14, 1960, for Pruning Apparatus. This invention is permanently mounted, and is not adapted as an attachment. The Whitmore machine also appears not to be capable of lowering the saw blade bearing arm to ground level with the blades in a horizontal orientation. The downwardly movement of the saw blade arm is limited by the height above ground of the trailer frame. Accordingly, this machine does not appear capable of orienting the saws so that they are at ground level.
U.S. Pat. No. 3,157,016 was granted on Nov. 17, 1964, to Leydig et al. for a Tree Topper With Reciprocating Cutter Boom. This machine, includes an articulated boom which carries a cutter arm having multiple saw blades. The cutter arm is raised and extended from the front of a self-propelled vehicle, such as a tractor, however the cutting apparatus is not an add-on that can be adapted to various vehicles. Additionally, in the Leydig invention the cutting apparatus is carried on the front of the vehicle and, is not borne laterally on the vehicle and thus would be unable to prune the lower sides of hedges.
A second patent was issued on Jul. 6, 1965, to Leydig as U.S. Pat. No. 3,192,695 for Tree Trimming Machine Or the Like. This machine is somewhat different from that of the previous Leydig patent, but is also a dedicated piece of equipment rather than an attachment adaptable to various vehicles. The cutter arm in this machine is capable of trimming bushes in a direction lateral to the direction of travel of the machine on the side of the vehicle. The cutting arm may also be tilted, but appears incapable of being extended to ground level.
A third patent to Leydig et al., U.S. Pat. No. 3,487,615 dated Jan. 6, 1970 is for Double-Boom Hedger. This is an interesting machine in which the vehicle resembles a bulldozer having two cutting arms connected forward of the vehicle. The cutting arms hydraulically extend upwardly, and may also be deployed laterally from the vehicle; however, the cutting arms cannot be tilted sufficiently to reach ground level.
U.S. Pat. No. 4,592,398 was issued on Jun. 3, 1986, to Golob et al. for Continuous Tree Harvestor [sic]. This invention appears directed to the cutting, harvesting and bundling of small trees such as Christmas trees. The cutting apparatus is positioned along the front of the vehicle and at relatively close to ground level but does not have the capability of being turned sideways relative to the vehicle.
Grant received U.S. Pat. No. 5,430,999 on Jul. 11, 1995, for Tree Trimming And Pruning Machine. This invention provides a cutting arm bearing multiple saw blades. The cutting arm is extendable hydraulically to reach the tops of trees and the blades may be turned so as to be oriented horizontally, However this machine cannot cut a vertical swath beside the vehicle as the hydraulic arm extends only directly ahead of the vehicle and not beside it.
Industrial Vehicle With Adjustable Boom Members to Edwards, U.S. Pat. No. 6,085,505, dated Jul. 11, 2000, describes a machine that is dedicated to cutting and is not an attachment for a pre-existing vehicle. Saw blades are borne on a hydraulically extendable boom and the cutting arm includes a pivot linkage that allows the blades to be turned from a vertical alignment to a horizontal alignment allowing the topping of trees.